JP2001350548A - Power control circuit of external storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power control circuit of an external storage device which can turn off the electric power after securely writing data to an external storage unit. SOLUTION: This circuit is equipped with an external storage unit 10 which stores data, a 1st interface which is connected to the external storage unit 10, a 2nd interface for connection with external equipment, a device which performs conversion between the data formats of the 1st and 2nd interfaces, a controller 28 which controls the operation of the whole circuit, an internal switch 35 for supplying the electric power to the external storage unit 10, and an external switch 22 for supplying a power-ON signal; and the controller 28 issues, when it is turned ON, some command to the 1st interface once detecting the external switch 22 being turned on and releases the internal switch 35 when a specific response is sent back from the external storage unit 10, thereby turning off the power source.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a power supply control circuit for an external storage device, and more particularly, to a power supply control circuit for an external storage device such as a personal computer (hereinafter abbreviated as a personal computer or a PC).

[0002]

2. Description of the Related Art External storage devices of personal computers, such as MOs (magneto-optical disk devices), HDDs (fixed disk devices), and CD-R / Ws, which have a modern interface such as USB and IEEE1394, have been actively appearing. FIG. 10 is a diagram showing a personal computer and an external storage device. In the figure, reference numeral 1 denotes a personal computer, which is connected to an external storage device 2 via a USB cable 3.

Many of these external storage devices are compatible with existing ATs.
External storage units with interfaces such as API and SCSI (so-called built-in MO drive, HDD, C
In many cases, a bridge system is added to (DR / W). The reason is as follows.

The development and mass production of an external storage unit having a new interface requires enormous cost and time. It is not currently possible to decide which of the new interfaces will become mainstream.

[0005] For the above reasons, ATAPI, SC
This is because it is more advantageous to develop or purchase a bridge system that converts SI into USB, IEEE1394, or the like, and to attach this externally.

FIG. 11 is a diagram showing an example of the external configuration of an external storage device with a USB or IEEE 1394 interface. The bridge system 2 is connected to the conventional external storage unit 10.
By adding 0, the conventional external storage unit 10 can be used. The bridge system 20 is realized by attaching various necessary components to a substrate. In the bridge system 20, 21 is a power jack, 22
Is a power switch, 23 is a connector such as USB or IEEE1394, and 24 is an interface such as SCSI or ATAPI, which is connected to the bridge system 20.
By providing the bridge system in this way, a storage unit using an existing SCSI or ATAPI interface can be used as a storage device compatible with USB and IEEE1394.

With the speeding up of personal computers and the speeding up of interfaces, speeding up of external storage units is also desired. Therefore, by temporarily storing data to be transferred by loading a high-speed semiconductor memory called a cache, which is faster than the MO, HDD, and CD-R / W, the access as an external storage device is apparently faster. PC can be released quickly.

FIG. 12 is a block diagram showing a conventional configuration example of an external storage device with a USB or IEEE 1394 interface. The same components as those in FIG. 10 are denoted by the same reference numerals. External storage unit 10 and bridge system 20
Are connected via a cable 25. Reference numeral 24 denotes a SCSI interface to which the cable 25 is connected.

In the bridge system 20, 26 is S
A CSI controller (first interface controller) 27 is a USB controller (second interface controller) connected to the SCSI controller 26. 28 is a SCSI controller 26 and USB
The control device connects the controllers 27 via the data bus 30. As the control device 28, for example, a CP
U is used.

2j is the SCSI controller 26 and SC
This is a first interface signal flowing between the SI interfaces 24. A personal computer 1 is connected to a USB connector 23. 2k is USB controller 27 and USB
This is a second interface signal flowing between the connectors 23.

Reference numeral 4 denotes a power source, and reference numeral 21 denotes a power jack to which the power source 4 is connected. Power input from the power jack 21 is supplied to the inside of the bridge system via a power switch 22. Reference numeral 29 denotes a bridge power supply. Power for operating the bridge system 20 is supplied from the power supply 29. The power source is connector 31 and connector 3
2 and the external storage unit 10 via the power supply line 36.
Also supplied to the side.

In the device configured as described above, the control device 28 performs mutual conversion between the USB interface and the SCSI interface via the first interface control signal 2h and the second interface control signal 2i and the data bus 30. . Thus, the data from the personal computer 1 enters the bridge system 20 from the USB controller 27, is converted into SCSI interface data, and is written to the external storage unit 10. That is, it becomes possible to read and write data in the external storage unit 10 using the conventional SCSI interface using the USB interface.

[0013]

[Problems to be Solved by the Invention] USB, IEEE13
94 has a hot plug function (a function that can turn off the power when not in use), and the power can be turned off at any time when the device is not used. However, when copying a large file from the personal computer 1, the external storage unit having the cache notifies the personal computer 1 of the completion of copying when all file transfers are completed including the amount stored in the cache.

The personal computer 1 displays or hides a dialog or the like on the screen to notify the user that the copying has been completed. However, there is a case where the writing operation is not actually completed just by actually being stocked in the cache. If the power is turned off at this time, the unwritten data stored in the cache is erased.

In order to prevent such an accident, Japanese Patent Laid-Open Publication No.
There is a technique described in Japanese Patent No. 5715. However, in the present invention, the external storage unit 10 also needs busy notification means. Therefore, the existing external storage unit 10
However, there is a problem that the method cannot be applied to an external storage unit having a bridge system.

The present invention has been made in view of such a problem, and provides a power supply control circuit of an external storage device which can reliably write data to an existing external storage unit and then turn off the power supply. It is intended to be.

[0017]

According to a first aspect of the present invention, there is provided an external storage unit for storing data, a first interface connected to the external storage unit, and an external device. A second interface, the first interface;
For converting the data formats of the first interface and the second interface, a control device for controlling the overall operation, an internal switch for supplying power to the external storage unit, and an external switch for supplying a power on / off signal When the control device detects that the external switch has been pressed when the power is on, the control device issues a command in the first interface, and when a specific response is returned from the external storage unit, The switch is released to turn off the power.

With this configuration, when a specific response returned from the external storage unit is received when all data has been written to the external storage unit, the power is turned off. The power can be turned off after data is written.

(2) In the invention according to claim 2, when the control device detects that the external switch is pressed when the power is turned on, a command or data for the external storage unit is transmitted from the second interface. It is confirmed that there is no communication for a predetermined time, and when there is no communication for a predetermined time, a command in the first interface is issued, and when a specific response is returned from the external storage unit, the internal switch is released and the power is turned off. And

With this configuration, when there is no command from the second interface to the external storage unit for a certain period of time, a specific response returned from the external unit when all data is written to the external storage unit Then, since the power is turned off, the power can be turned off after all the data sent by the personal computer are securely written to the external storage unit.

(3) The invention according to claim 3 is characterized in that when there is no command from the second interface to the external storage unit for a predetermined time, the internal switch is released to turn off the power. I do.

With this configuration, when there is no request from the second interface to the external storage unit for a certain period of time, the power can be turned off to suppress unnecessary power consumption of the external storage unit.

(4) In the invention according to claim 4, the external storage unit is a removable media drive unit, and when the medium has not been in the external storage unit for a predetermined time, the internal switch is released. And turning off the power.

With this configuration, when the state where the removable medium is not in the external storage unit continues for a certain period of time, the power is turned off, so that unnecessary power consumption of the external storage unit can be suppressed.

(5) A fifth aspect of the present invention is characterized in that a time measuring means for measuring time is provided, and the power is turned on or off at a predetermined time. With this configuration, automatic backup can be performed in cooperation with the backup program of the personal computer.

(6) According to a sixth aspect of the present invention, when the power is turned on, a command in the first interface is issued when the external switch is pressed, and a specific response is returned from the external storage unit. The user can instruct through the second interface whether to turn off the power or to turn off the power as soon as the external switch is pressed.

According to this structure, the personal computer sets whether to turn off the power after a specific response is returned from the external storage unit or to turn off the power immediately after the external switch is pressed. Can be
The power-off control can be performed as needed.

(7) In the invention according to claim 7, when the power is turned on, when the external switch is pressed, it is confirmed for a fixed time that there is no command to the external storage unit from the second interface, and When there is no said 1st
Issue a command in the second interface, and select whether to turn off the power when a specific response is returned from the external storage unit or to turn off the power immediately after the external switch is pressed through the second interface. And can be instructed.

With this configuration, when there is no command in the external storage unit for a certain period of time, the power is turned off after a specific response is returned from the external storage unit, or immediately after the external switch is pressed. The user can select whether or not to turn off the power and set the time from a personal computer, and can perform power-off control as needed.

(8) According to the invention described in claim 8, when there is no request from the second interface to the external storage unit for a certain period of time, it is instructed via the second interface whether to turn off the power. It is characterized by being able to.

With this configuration, when there is no request for the external storage unit for a certain period of time, it is possible to select whether or not to turn off the power and set the time from the personal computer. Can be.

(9) In the invention according to claim 9, the external storage unit is a removable media drive unit, and when a state in which the medium is not in the external storage unit has elapsed for a predetermined time, the power is turned off. It is characterized in that selection of whether or not can be instructed through the second interface.

With this configuration, when the removable medium has not been in the external storage unit for a certain period of time, the user can select whether or not to turn off the power and set the time from the personal computer. Power off control can be performed.

(10) The invention according to claim 10 is characterized in that setting of a fixed time can be instructed through the second interface. With such a configuration, the setting of the fixed time can be instructed from the personal computer, and the power on / off control can be performed as needed.

(11) In the invention according to claim 11, when the power is turned on, when the external switch is pressed, the control device notifies the external device through the second interface, and in accordance with the instruction of the external device. The power supply is turned off.

With this configuration, the power can be turned off from an external device.

[0037]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention. The same components as those in FIG. 12 are denoted by the same reference numerals. In the embodiment shown in FIG. 12, the fourth embodiment is different from the configuration shown in FIG.
The configuration is different from that shown in the figure, and the other components are the same as those in FIG. External storage unit (for example, MO
The drive 10 and the bridge system 20 are connected by a SCSI cable 25 and a power supply line 36.

The power from the power supply 4 enters the bridge system 20 via the power jack 21. As for the power supply that has entered the bridge system 20, a power supply for operating the bridge system 20 is created by the bridge power supply 29. On the other hand, the power supplied from the power jack 21 enters the external storage unit 10 via the power supply line 36 via the internal switch 35.

The personal computer 1 is connected to the USB
It is connected to the controller 27. The USB controller 27 is connected to the SCSI controller 26 via the data bus 30. The control device 28 is connected to the SCSI controller 26 and the USB controller 27 via the data bus 30. The control device 28
Outputs an on / off control signal 2g to the internal switch 35.

The power switch (external switch) 22 supplies a low-active signal to the control device 28 as shown in FIG. That is, when the external switch 22 is pressed,
An “L” level signal is applied to control device 28. 5
Is an LED controlled by a control device (hereinafter referred to as CPU) 28. The LED 5 indicates power on / off.

Commands and data transmitted from the personal computer 1 through the USB cable are transmitted to the USB controller 27.
Is converted from the USB protocol into a form that can be processed by the CPU 28. This is used by the CPU 28 for the SCSI controller 2
6 and convert it to a format that can be handled. The SCSI controller 26 converts the data into the SCSI protocol and sends it to the external storage unit 10. The transfer of commands and data from the external storage unit 10 to the personal computer 1 follows the reverse. Thus, the conversion device described in claim 1 is defined as U
The SB controller 27, the SCSI controller 26, and the CPU 28 are shown. The operation of the thus configured device will be described below with reference to the flowchart of FIG.

FIG. 2 is a flowchart showing a first operation example of the present invention. When the power supply 4 is connected to the bridge system 20 (S11), power is supplied from the bridge power supply 29 and the CPU 28 starts operating. The CPU 28 initializes the bridge system 20 (S12). Then, C
The PU 28 waits until the external switch 22 is pressed (S1).
3).

When the external switch 22 is pressed, the CPU 2
8 turns on the internal switch 35 and turns on the external storage unit 1
0 (S14), and turns on the LED 5 (S14).
15). When the LED 5 is turned on, it can be recognized that the power has been turned on.

Thereafter, the CPU 28 performs a bridging operation using the USB controller 27 and the SCSI controller 26, and makes the personal computer 1 and the external storage unit 10 communicate well (S16). When the internal switch 35 is on and the external switch 22 is pressed (S17), CP
U28 enters post-processing for powering off (S18).

In the post-processing, the CPU 28 blinks the LED 5 to notify the operator that the post-processing has been started (S28).
21). Thereafter, it is checked for a predetermined time whether or not there is a data copy request from the personal computer 1 (S22). Data sent from the personal computer 1 is divided into small blocks and sent. Therefore, it is necessary to check in step S22 whether transmission of all data from the personal computer 1 has been completed.

When the data transfer request is received again from the personal computer 1, the flow returns to step S16 to perform the bridging operation. If there is no data transfer request, the CPU 28 checks, for example, whether one second has elapsed using a soft timer (S23). If there is no data transfer request for one second or longer, the CPU 28 next issues a specific command
It is issued to the external storage unit 10 via the SI controller 26 (S24).

The reason is that the external storage unit 10
If there is a cache in the non-volatile memory (actual H
D, MO, CD itself), the external storage unit 10 can store the bridge system 2 even if the writing process has not been completed.
This is because it informs 0 through the SCSI controller 26 that the processing has been completed.

The CPU 28, having received the processing end notification,
It is necessary to recognize that all data to be written to a cache (not shown) in the external storage unit 10 has been collected, and then to surely detect that the writing to the storage medium has been completed. Therefore, for example, when the first interface is SCSI, the CPU 28
own) command is issued (S24). Here, the spin down command is, for example, a signal for stopping the rotation of the MO. When the CPU (not shown) in the external storage unit 10 receives the spin-down command and finishes writing data to the storage medium, it returns a GOOD condition to the bridge system 20. Here, the command is not limited to only spin down. If it is a removable media drive unit, it may be an eject. However, the medium is ejected last.

When the GOOD condition is returned from the external storage unit 10 (S25), the CPU 28
D5 is turned off (S26), and the internal switch 35 is turned off (S27). In this state, power supply to the external storage unit 10 is cut off. Next, returning to step S13,
Wait for the external switch 22 to be pressed.

According to this embodiment, when a specific response (here, GOOD condition) returned from the external storage unit 10 is received when all data has been written to the external storage unit 10, the power supply is turned off. Since the power is turned off, the power supply can be turned off after all the data sent by the personal computer 1 are securely written in the external storage unit 10.

FIG. 3 is a block diagram showing a second embodiment of the present invention. 1 are denoted by the same reference numerals. In this embodiment, the external storage unit 1
The circuit when the ATAPI interface is used as 0 is shown. In this case, the first interface controller as shown in FIG. 1 becomes unnecessary. The interface controller 27 is connected to the connector 2 via the interface unit 33.
3 and the personal computer 1.

Here, the interface controller 2
7 is used for IEEE1394. I
Since the communication line for EEE1394 includes a power supply line therein, if power can be supplied from the personal computer 1, the power supply line is also connected to the connector 23. In this case, the power supply is connected to the power supply line via the backflow preventing diode D2. On the other hand, the power supply from the power supply 4 is also connected to the power supply line via the power supply jack 21 and the backflow prevention diode D1. As a result, power for operating the bridge system 20 can be supplied from the personal computer 1 side and the power supply 4 side, and the power supply can be operated in parallel via the backflow prevention diodes D1 and D2.

The control device (CPU) 28 includes a data bus 3
0 through the interface controller 27 and the ATA
It is connected to the PI interface 24. In the system configured as described above, a case where the bridge power supply 29 is supplied by an ON signal from the external switch 22 will be considered. When a request to write data from the personal computer 1 to the external storage unit 10 is issued, data conforming to IEEE 1394 from the personal computer 1 is transmitted to the interface controller 2 via the interface unit 33.
7 and exchanges interface control signals with the CPU 28 to convert data conforming to IEEE 1394 into ATAPI data. ATA
The data converted into the PI format is temporarily stored in a cache of the external storage unit 10 and then written to a storage medium.

Here, when all data is stored in the cache, the bridge system 20
, A processing end signal is output. The CPU 28 that has received the processing end signal issues a specific command (for example, Spindown) to the external storage unit 10. When the external storage unit 10 receives this command, when the data writing to the storage medium is completed, the internal C
Data write from PU completed (GOOD condition)
A signal is output. When receiving the GOOD condition signal, the CPU 28 controls the internal switch 35 to release the contact. As a result, the power supplied to the external storage unit 10 is turned off.

Also in the case of this embodiment, when a specific response (here, GOOD condition) returned from the external storage unit 10 is received when all data has been written to the external storage unit 10, the power supply is turned off. Since the power is turned off, the power supply can be turned off after all the data sent by the personal computer 1 are securely written in the external storage unit 10.

According to the above-described embodiment, there is an effect that the power control can be performed without changing existing external storage units or software of personal computers. FIG. 5 is a block diagram showing a third embodiment of the present invention. 1 are denoted by the same reference numerals. In the figure, a timer 37 provided in the bridge system 20 is connected to the CPU 28. The timer 37
It keeps time and is backed up by a battery. Therefore, even if the power of the circuit is cut off, the timer 37 keeps counting time. Other configurations are exactly the same as those in FIG. The operation of the present invention will be described using the system configured as described above.

FIG. 6 is a flowchart showing a second operation example of the present invention. When the power supply 4 is connected to the bridge system 20 (S11), power is supplied from the bridge power supply 29, and the CPU 28 starts operating. The CPU 28
The bridge system 20 is initialized (S12). Thereafter, the CPU 28 waits until the external switch 22 is pressed (S13).

When the external switch 22 is pressed, the CPU 2
8 turns on the internal switch 35 and turns on the external storage unit 10.
Is supplied (S14), and the LED 5 is turned on (S1).
5). After that, the CPU 28
A bridge operation is performed using the USB controller 27 and the USB controller 27, and the personal computer 1 and the external storage unit 10 are successfully communicated (S16).

Next, when the bridge operation is completed, the CPU
28 goes to read the time of the timer 37. On the other hand, CPU2
8 checks whether the external switch 22 has been pressed (S17a). If the external switch 22 has been pressed, post-processing is started (S18). If the external switch 22 is not pressed, the CPU 28 counts the time without access from the personal computer 1 using the timer 37 (S17b).
In other words, the time at the time of the last access is read, and the elapsed time thereafter is counted. If there is access from the personal computer 1, the CP
U28 ignores the read time information.

If there is an access from the personal computer 1, the flow returns to step 16 to perform a bridge operation. If 15 minutes have passed without access from the personal computer 1,
The CPU 28 enters post-processing (S18). The post-processing is shown in FIG.
Is exactly the same as the post-processing shown in FIG. The connection from FIG. 4 also corresponds to the sequence of the post-processing in FIG.

According to this embodiment, when there is no request from the second interface to the external storage unit for a certain period of time, the power can be turned off to suppress unnecessary power consumption of the external storage unit.

FIG. 7 is a flowchart showing a third operation example of the present invention. FIG. 5 is used as the system configuration. When the power supply 4 is connected to the bridge system 20 (S
11), power is supplied from the bridge power supply 29,
U28 starts operating. The CPU 28 initializes the bridge system 20 (S12). After that, the CPU 28
Waits for the external switch 22 to be pressed (S13).

When the external switch 22 is pressed, the CPU 2
8 turns on the internal switch 35 and turns on the external storage unit 10.
Is supplied (S14), and the LED 5 is turned on (S1).
5). After that, the CPU 28
A bridge operation is performed using the USB controller 27 and the USB controller 27, and the personal computer 1 and the external storage unit 10 are successfully communicated (S16).

Next, when the bridge operation is completed, the CPU
28 checks whether the external switch 22 has been pressed (S17a). In this case, the CPU 28 stores the last access time from the personal computer 1. If the external switch 22 has been pressed, post-processing is started (S18). If the external switch 22 is not pressed, it is checked whether 15 minutes have passed without access from the personal computer 1 (S17b). The elapsed time of 15 minutes is counted by the CPU 28 reading the time information of the timer 37 and subtracting the last access time from the personal computer 1.

When 15 minutes have passed without access from the personal computer 1, post-processing is started (S18). If 15 minutes have passed without access from the personal computer 1, the CPU 2
In step S17c, it is checked whether five minutes have passed without a removable medium (hereinafter, abbreviated as medium). In this case, the CPU 28 does not read the timer 37 if a medium is inserted. When the medium is pulled out, the CPU 28 goes to read the timer 37 and stores the time at that time. And no media is 5
After a lapse of minutes, post-processing is started (S18). The sequence of the post-processing is exactly the same as that shown in FIG. The connection from FIG. 4 also corresponds to the sequence of the post-processing in FIG.

According to this embodiment, when the state where the removable medium is not in the external storage unit 10 continues for a predetermined time or more, the power is turned off.
Useless power consumption of the external storage unit 10 can be suppressed.

FIG. 8 is a flowchart showing a fourth operation example of the present invention. FIG. 5 is used as the system configuration. When the power supply 4 is connected to the bridge system 20 (S
11), power is supplied from the bridge power supply 29,
U28 starts operating. In this case, the CPU 2
It is assumed that a reservation time is stored in advance in 8. CP
U28 initializes the bridge system 20 (S1).
2). Thereafter, the CPU 28 waits until the external switch 22 is pressed (S13a). If the external switch 22 has been pressed, the process proceeds to step S14 and subsequent steps.

When the external switch 22 is not pressed,
Wait for the external switch 22 to be pressed. During this time, the timer 37 is read, and when the time of the timer 37 reaches the reserved time, the CPU 28 detects this and turns on the internal switch 35 (S13). As a result, power is supplied to the external storage unit 10. At the same time, LE
D5 is turned on (S15). After that, the CPU 28
A bridge operation is performed using the SI controller 26 and the USB controller 27, and the personal computer 1 and the external storage unit 10 are successfully communicated (S16).

Next, when the bridge operation is completed, the CPU
28 checks whether the external switch 22 has been pressed (S17a). In this case, the CPU 28 stores the last access time from the personal computer 1. If the external switch 22 has been pressed, post-processing is started (S18). If the external switch 22 is not pressed, it is checked whether 15 minutes have passed without access from the personal computer 1 (S17b). The elapsed time of 15 minutes is counted by the CPU 28 reading the time information of the timer 37 and subtracting the last access time from the personal computer 1.

When 15 minutes have passed without access from the personal computer 1, post-processing is started (S18). If 15 minutes have passed without access from the personal computer 1, the CPU 2
In step S17c, it is checked whether five minutes have passed without a removable medium (hereinafter, abbreviated as medium). In this case, the CPU 28 does not read the timer 37 if a medium is inserted. When the medium is pulled out, the CPU 28 goes to read the timer 37 and stores the time at that time. And no media is 5
After a lapse of minutes, post-processing is started (S18). The sequence of the post-processing is exactly the same as that shown in FIG. The connection from FIG. 4 also corresponds to the sequence of the post-processing in FIG.

According to this embodiment, automatic backup can be performed in cooperation with the backup program of the personal computer 1. FIG. 9 is a flowchart showing a fifth operation example of the present invention. In this embodiment, the power of the external storage device can be turned off from an external device (for example, a personal computer). The figure shows post-processing, and is the same as that described above up to post-processing. In the present invention, the control device (CPU) 2
8 issues a spin-down command. In the present invention, a spin-down command is issued from an external device (for example, a personal computer). Also, the personal computer instructs permission to turn off the power. FIG. 1 is used as the system configuration.

When the post-processing is started (S20), the LED 5 is blinked to notify that the post-processing is started (S21). When the external switch 22 is pressed, the CPU 28 notifies the personal computer 1 via the second interface (USB interface) that the switch has been pressed (S23).

The CPU 28 continues the bridging operation until the personal computer 1 gives an instruction to turn off the power (S24, S2).
5). When all data has been ejected, the personal computer 1 issues a spin down command to the external storage device.
When the GOOD condition is returned from the external storage device, it can be recognized that all data has been written to the non-volatile memory, and the CPU 28 of the external storage device is instructed to turn off the power (S24, S25). The CPU 28 turns off the LED 5 in response to the instruction from the personal computer 1 (S2).
6), the internal switch 35 is released to turn off the power (S27).

According to this embodiment, the power-off control can be performed from an external device (for example, a personal computer). In the present invention, the user can select whether or not to use the function of the present invention by operating utility software or the like from a personal computer, and can instruct the setting of the waiting time.

For example, when the power is turned on, the external switch 22
When a command is issued, a command in the first interface (SCSI interface) is issued, and when a specific response is returned from the external storage unit 10, the power is turned off, or immediately after the external switch 22 is pressed. The user can be instructed via the second interface to select whether to turn off the power.

With this configuration, the personal computer selects whether to turn off the power after a specific response is returned from the external storage unit 10 or to turn off the power immediately after the external switch 22 is pressed. It can be set from 1 and power-off control can be performed as needed.

When the power is turned on, when the external switch 22 is pressed, it is confirmed that there is no command from the second interface (USB interface) to the external storage unit 10 for a certain period of time. The second option is to issue a command in the first interface and turn off the power when a specific response is returned from the external storage unit 10 or to turn off the power immediately after the external switch 22 is pressed. Instructions can be made via an interface.

With this configuration, when there is no command in the external storage unit 10 for a certain period of time, the power is turned off after a specific response is returned from the external storage unit 10, or the external switch 22 is pressed. As soon as the power is turned off, the user can select or set the time from the personal computer 1, and the power can be turned off as needed.

When there is no request from the second interface (USB interface) to the external storage unit 10 for a certain period of time, selection of whether to turn off the power and setting of the certain period are instructed through the second interface. You can do it.

With this configuration, when there is no request for the external storage unit 10 for a certain period of time, it is possible to select whether or not to turn off the power and to set the time from the personal computer. be able to.

The external storage unit 10 is a removable medium.
When a state in which the power supply has not been entered has passed for a predetermined time, the user can be instructed via the second interface to select whether or not to turn off the power.

With this configuration, when the removable medium has not been in the external storage unit for a certain period of time, the user can select whether or not to turn off the power and set the time from the personal computer. Power off control can be performed.

Further, it is possible to make an instruction for setting a fixed time via the second interface. With such a configuration, the setting of the fixed time can be instructed from the personal computer, and the power on / off control can be performed as needed.

[0084]

As described above, according to the present invention, the following effects can be obtained. (1) According to the first aspect of the invention, when all data is written to the external storage unit, the power is turned off when a specific response returned from the external storage unit is received. The power can be turned off after the data is reliably written.

(2) According to the second aspect of the present invention, the second
When there is no command to the external storage unit from the interface for a certain period of time, when all data is written to the external storage unit and a specific response returned from the external unit is received, the power is turned off. The power can be turned off after all the data sent by the personal computer is securely written to the storage unit.

(3) According to the third aspect of the present invention, the second
When there is no request from the interface to the external storage unit for a certain period of time, the power can be turned off to suppress unnecessary power consumption of the external storage unit.

(4) According to the fourth aspect of the present invention, when the state where the removable medium is not in the external storage unit continues for a predetermined time, the power is turned off,
Wasteful power consumption of the external storage unit can be suppressed.

(5) According to the fifth aspect of the present invention, automatic backup can be performed in cooperation with a backup program of a personal computer. (6) According to the invention described in claim 6, it is possible to select whether to turn off the power after a specific response is returned from the external storage unit or to turn off the power immediately after the external switch is pressed. Can be set from a PC,
The power-off control can be performed as needed.

(7) According to the seventh aspect of the present invention, when there is no command in the external storage unit for a predetermined time, the power is turned off after a specific response is returned from the external storage unit, or the external switch is turned off. The user can select whether or not to turn off the power as soon as the button is pressed and set the time from a personal computer, and can perform power-off control as needed.

(8) According to the invention described in claim 8, when there is no request for the external storage unit for a certain period of time, it is possible to select whether or not to turn off the power and set the time from the personal computer. Off control can be performed.

(9) According to the ninth aspect of the present invention, it is possible to select from the personal computer whether to turn off the power and set the time when a certain period of time has elapsed without the removable medium being in the external storage unit. Therefore, power-off control can be performed as needed.

(10) According to the tenth aspect,
A set time can be instructed from a personal computer, and power on / off control can be performed as needed. (11) According to the eleventh aspect, the power-off control can be performed from the external device.

As described above, according to the present invention, it is possible to provide a power supply control circuit for an external storage device which can write data to an external storage unit and then turn off the power supply. Further, the above power supply control can be performed without changing the software of the existing external storage unit.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating a first operation example of the present invention.

FIG. 3 is a block diagram showing a second embodiment of the present invention.

FIG. 4 is a diagram illustrating a configuration example of an external switch.

FIG. 5 is a block diagram showing a third embodiment of the present invention.

FIG. 6 is a flowchart showing a second operation example of the present invention.

FIG. 7 is a flowchart showing a third operation example of the present invention.

FIG. 8 is a flowchart showing a fourth operation example of the present invention.

FIG. 9 is a flowchart showing a fifth operation example of the present invention.

FIG. 10 is a diagram showing a personal computer and an external storage device.

FIG. 11 is a diagram illustrating an example of an external configuration of an external storage device with a USB or IEEE1394 interface.

FIG. 12 is a block diagram showing a conventional configuration example of an external storage device with a USB or IEEE1394 interface.

[Explanation of symbols]

 Reference Signs List 1 personal computer 4 power supply 5 LED 10 external storage unit 20 bridge system 21 power jack 22 external switch 23 connector 24 SCSI interface 25 cable 26 SCSI controller 27 USB controller 28 controller (CPU) 29 power supply for bridge 30 data bus 31, 32 connector 35 Internal switch 36 Power supply line

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G06F 1/00 334F 334G

Claims (11)

[Claims] An external storage unit for storing data; a first interface connected to the external storage unit; a second interface for connecting to an external device; A device for converting the data format of the interface, a control device for controlling the overall operation, an internal switch for supplying power to the external storage unit, and an external switch for supplying a power on / off signal, When the control device detects that the external switch has been pressed when the power is on, it issues a command in the first interface, and releases the internal switch when a specific response is returned from the external storage unit. A power supply control circuit for an external storage device, wherein the power supply control circuit is turned off. 2. When the control device detects that the external switch is pressed when the power is turned on, the control device confirms that there is no command or data for the external storage unit from the second interface for a predetermined time, and 2. The external storage according to claim 1, wherein a command in the first interface is issued when there is no time, and when a specific response is returned from the external storage unit, the internal switch is released and the power is turned off. The power control circuit of the device. 3. The apparatus according to claim 1, wherein when there is no command from the second interface to the external storage unit for a predetermined time, the internal switch is released to turn off the power. 3. A power supply control circuit for an external storage device according to claim 1. 4. The external storage unit is a removable media drive unit, and when a state in which the medium is not in the external storage unit has elapsed for a predetermined time, releasing the internal switch to turn off the power. 4. A power supply control circuit for an external storage device according to claim 1, wherein: 5. The power supply control of an external storage device according to claim 1, further comprising a time measuring means for measuring time, wherein the power is turned on or off at a predetermined time. circuit. 6. When the power is on, a command in the first interface is issued when the external switch is pressed, and when a specific response is returned from the external storage unit, the power is turned off or the external 2. The power supply control circuit for an external storage device according to claim 1, wherein a selection of whether to turn off the power supply as soon as a switch is pressed can be instructed through said second interface. 7. When the power is turned on, when the external switch is pressed, it is confirmed for a fixed time that there is no command from the second interface to the external storage unit, and when there is no fixed time, it is in the first interface. Command to issue a command via the second interface to turn off the power when a specific response is returned from the external storage unit or to turn off the power as soon as the external switch is pressed. 3. The power supply control circuit for an external storage device according to claim 2, wherein: 8. The apparatus according to claim 3, wherein when there is no request from said second interface to said external storage unit for a predetermined period of time, a selection as to whether to turn off the power can be instructed through said second interface. Power supply control circuit of the external storage device. 9. The external storage unit is a removable media drive unit, and when a state in which the medium has not been in the external storage unit has elapsed for a predetermined period of time, the second storage device determines whether or not to turn off the power. 5. The power supply control circuit for an external storage device according to claim 4, wherein the instruction can be made via an interface. 10. The power supply control circuit for an external storage device according to claim 5, wherein setting of a fixed time can be instructed through said second interface. 11. When the power supply is turned on, when the external switch is pressed, the control device notifies the external device through a second interface, and turns off the power supply according to an instruction of the external device. The power supply control circuit for an external storage device according to claim 1.